The Obamas, Prince Harry promoting Invictus Games

The 31-year-old Harry joined Michelle Obama at the Fort Belvoir military installation in Virginia to meet injured troops - and together promote the event. (AAP)

Prince Harry has been hosted at the Oval Office, after cheering a basketball game with the first lady, during a lightning visit to the United States to promote the 2016 Invictus Games.

Launched in London in 2014, the games for injured service personnel, championed by the Prince Harry, hold their second edition in Orlando in May next year.

The 31-year-old Harry joined Michelle Obama at the Fort Belvoir military installation in Virginia to meet injured troops - and together promote the event.

Sporting a blue suit - and beard - Harry sat beside the first lady through a game of wheelchair basketball, as she pumped up the room, saying: "It's a game, come on!"

Harry promised next year's games would be "four really intense days of sport", while Obama quipped she must "apologise to him in advance for all the gold metals America will win".

"I know everyone involved is working to raise the bar so that this event will keep getting bigger, and bigger every single year," she said.

Harry, who was to fly out later Wednesday (local time), headed from Virginia to the White House for an informal first meeting with the US president.

"We are very glad to support the Invictus Games," said Obama, who praised efforts "to make sure that we see not simply the sacrifices (service members) have made, but also the incredible contributions and strength and courage that they continue to display."

The president also thanked Harry for his service alongside US forces in Afghanistan, calling it "a testament to the special relationship, the incredible bond that we share between our two countries".

Harry told Obama that organisers had "huge amounts of fun" planning the games, which he said were inspired by the Warrior Games in the United States.

The 2014 Games brought together 413 wounded troops from 13 countries, doing battle across a range of sports.

For the 2016 edition in Orlando, organisers are preparing for some 500 athletes from 15 nations.